I have owned both shotguns. I love the superposed and they are a wounderful value at this time. Made in Beligum, very collectable. The BSS were made in Japan, very nice side by sides. I would go out and handle a BSS and if it is what you are looking for, buy it! Your 1952 Grade I in 90% condition would have a low interest value to a collector. You could perhaps trade even for a mint BSS 12 or 20Ga. Just a few ideas.
Sarge 105